Q: My iMac G5 keeps shutting down.
Recently a email link was clicked on and since then my wife has been having issues with her G5 shutting down. Sometimes the box will not completely boot at all and others it will boot up for a moment and then shut itself off.
I have looked for teh Flashback Trojan and appear to be clean. If i boot the box in safe mode when booted in safe mode all seems okay. I have also recently reset the PRAM and have had the machine up for a few minutes and it has not shut down yet.
I am runnig Mac OS X 10.5.8, I read a few threads and see that there is a newer virus out there beyond teh Flashback Trojan, are there any suggestons of things to look at to resolve this problem?
iMac, Mac OS X (10.5.8)
Posted on Jul 1, 2012 11:47 AM
I don't think Flashback affects PowerPC Macs, and it (or any malware) is unlikely to cause the symptoms you describe in any case. It is probably a coincidence that this problem seemed to start after an email link was clicked.
If this is an iMac G5, in addition to resetting PRAM, you should reset SMU (power management). This is the procedure for an iMac G5
http://support.apple.com/kb/HT1767
When you reconnect it back to power, if it was previously connected to a "power strip" of some type (especially if it's old or overcrowded), try connecting it directly to a wall outlet, by itself. Start it up with nothing else connected initially, then connect only a standard mouse and keyboard. Use it that way for a while, to see if there is improvement. Some USB devices (whether faulty or not) can cause "interference."
A problem with unexpected shutdown can be related to the iMac's power supply failing. When you start up in safe mode, some of the hardware (such as the graphics hardware) may he working at lower capacity, so it works more reliably.
If you have not already, you should back up the user data (while running in Safe Mode).
Posted on Jul 1, 2012 1:30 PM